Unifying the Processing of XML Streams and Relational Data Streams

Relational data streams and XML streams have previously provided two separate research foci, but their unified support by a single Data Stream Management System (DSMS) is very desirable from an application viewpoint. In this paper, we propose a simple approach to extend relational DSMSs to support both kinds of streams efficiently. In our Stream Mill system, XML streams expressed as SAX events, can be easily transformed into relational streams, and vice versa. This enables a close cooperation of their query languages, resulting in great power and flexibility. For instance, XQuery can call functions defined in our SQLbased Expressive Stream Language (ESL) using the logical/physical windows that have proved so useful on relational data streams. Many benefits are also gained at the system level, since relational DSMS techniques for load shedding, memory management, query scheduling, approximate query answering, and synopsis maintenance can now be applied to XML streams. Moreover, the man...

• Type: Conference
• Year: 2006
• Where: ICDE
• Authors: Xin Zhou, Hetal Thakkar, Carlo Zaniolo
• Keywords: Database, ICDE 2006, Relational Data Streams, Relational Streams, XML Streams